The question
For any capability, like auth, search, or payments, you can build it in house or buy an existing library, product, or managed service. The right answer depends on whether the capability is core to your value.
Reasons to buy
- The problem is solved and commoditized, so reinventing it wastes time.
- A managed service removes operational burden like patching and scaling.
- You ship faster and focus engineers on what makes your product unique.
Reasons to build
- The capability is a core differentiator where being better than off the shelf is the whole point.
- No product fits your specific constraints, or the cost at your scale is prohibitive.
- You need control the vendor will not give, such as data locality or deep customization.
Hidden costs both ways
- Buying adds lock in, integration work, and ongoing license cost.
- Building adds long term maintenance, on call burden, and the risk of a half finished tool.
Buy your undifferentiated heavy lifting and build what makes you special.
Key idea
Buy commoditized capabilities to ship faster and build only what is a true differentiator, weighing lock in against long term maintenance.